Process for breaking petroleum emulsions



Patented July 22, 1941 PROCESS FOR BREAKING PETROLEUM EMULSIONS MelvinDe Groote, University City, and Bernhard Keiser, Webster Groves, Mo.,assignors to Petrolite Corporation, Ltd., Wilmington, DeL, a

corporation of Delaware- No Drawing. Application June 27, 1940, SerialNo. 342,719

11 Claims.

This invention relates primarily to the resolution of petroleumemulsions.

One object of our invention is to provide a novel process for resolvingpetroleum emulsions of the water-in-oil type, that are commonly referredto as cut-oil, roily oil, emulsified oil, etc., and which comprise finedroplets of naturally-occurring waters or brines dispersed in a more orless permanent state throughout the oil which constitutes the continuousphase of the emulsion.

Another object of our invention is to provide an economical and rapidprocess for separating emulsions which have been prepared undercontrolled conditions from mineral oil, such as crude petroleum andrelatively soft waters or weak brines. Controlled emulsification andsubsequent demulsification under the conditions just mentioned is ofsignificant value in removing impurities, particularly inorganic salts,from pipeline oil.

The material or composition of matter which we prefer to use as thedemulsifier of our process, canv be produced by reacting a polybasiccarboxy acid or its functional equivalent, such as the anhydride, andmore particularly phthalic anhydride, with products of the kindderivable by an acylation reaction between a ricinoleic acid body and anacylation-reactive amine of the type:

in which B is selected from the class consisting of hydroxy hydrocarbonradicals, ether-type oxyhydrocarbon radicals, and hydroxylated ethertypeoxyhydrocarbon radicals; T may be selected from the class consisting ofhydrogen atoms, alkyl radicals, and radicals of the kind exemplified byB; and Z'represents 'a member of, the class consisting of hydrogenatoms, hydrocarbon radicals, oxyhydrocarbon radicals, and radicalsderived by removal of an alpha hydrogen atom from a carboxy acid ester.

Although such compounds may be obtained in various ways, obviously theyare most readily obtainable by first preparing the acylation reactionproduct of the kind described, for instance, the product obtained byreaction between ricinoleic acid and tris(hydroxymethyl) aminomethane ora homologue or-analogue thereof. Thus, reactions of the kind justreferred to, i. e., intended to produce an intermediate product, are

concerned with the introduction of an acyl radical, for example, aricinoleyl radical into an am ne of the kind mentioned. Such acylationmay take place by virtue of an amidification reaction, or by virtue ofan esterification reaction. For the sake of convenience, in the heretoappended claims, both types of reactions, amidification andesterification, will be referred to as acylation reactions. In otherwords, reference to an acylation reaction is not intended todifferentiate between whether an esterification reaction takes place, oran amidification reaction takes place, or if both take place.

Ricinoleic acid is most readily available in the form of castor oil,which contains about triricinolein. Insteadof ricinoleic acid, one mayemploy monoricinolein, diricinolein, methyl ricinoleate, ethylricinoleate, benzyl ricinoleate, cyclohexyl ricinoleate, etc. Similarly,one may employ polyricinoleic acid, such as diricinoleic acid,triricinoleic acid, and tetraricinoleic acid; or one may employ thedibasic type of diricinoleic acid. Obviously, ricinoleic acid esterscanbe derived from polyhydric alcohols other than glycer'ol, forinstance, from the various glycols, polyglycols, polyglycerols, methylglycerol, and the like. Ordinarily, one would employ the cheapest sourceof the ricinoleic acid radical, which is castor oil. Slightly blowncastor oil or the like may be used.

Castor oil can be treated with one mole or two moles of glycerol, or anyintermediate quantity, to produce a material consisting largely ofdiricinolein, monoricinolein, and some triricinolein, with perhaps asmall amount of free glycerol. Such material is commonly referred to assuperglycerinated castor oil or superglyc-v erinated triricinolein. Suchmixture may be considered as a typical ricinoleic acid body.

Having indicated the variety of ricinoleic acid compounds which may beemployed, reference will now be made to the type of amine intended forreaction. It is well known that paraflins can be treated with nitricacid, so as to produce nitroparaifins or nitrites. Such nitroparaflinscan be treated with aldehydes, particularly aliphatic aldehydes, havingfour carbon atoms or less, so as to produce nitroparaffins, in whichone, two or three hydroxyl alkyl radicals have been introduced, andparticularly characterized by the fact that such nitroparafiins may havetwo or three alkylol groups attached to the same carbon atom. Suchnitroparaffins can readily beconverted into the corresponding amine. SeeChemical Industries, volume 45, No. '7',

pages 664668, December, 1939. See also Industrial and EngineeringChemistry, volume 32, No. 1, page 34.

Some known examples of. .amines of the kind described are:

Such amines may be indicated by the following formula type:

2-amlno-2-mctliyl-l,3-propanedi0l NHz in which D represents a divalentradical, such as the methylene radical, and T may be a hydrogen atom orthe same as OH.D, or may represent a monovalent hydrocarbon radical,particularly an alkyl radical. In other words, the nature of T may varywith the particular paraffin selected, and the molal reaction ratiobetween the nitroparaflin and aldehyde, in the event the parafiin ismethane. Needless to say, such reactions between an aldehyde and anitroparaflin may yield a monohydric alcohol, as distinguished from anitro-diol or nitro-triol, in the event the paraifin is methane. Suchmonohydroxylated compound can be converted into an alkylolamine. Suchalkylolamine, as, for example, Z-amino-l-butanol, is not hereincontemplated for reaction intended to produce condensation products oresterification products of the kind previously described, i. e., thetype to be subsequently reacted with phthalic anhydride orhexahydrobenzaldehyde, give very inferior reaction with thenitroparaflins, formaldehyde, acetaldehyde, and butyraldehyde are to bepreferred, with formaldehyde being particularly desirable. Cyclicaldehydes, such as benzaldehyde, or hexa hydrobenzaldehyde, give veryinferior yields.

Having obtained an amine of the kind above described, which is a primaryamine, it can readily be converted into a secondary or tertiary amine byany of the procedures commonly employed for introducing an alkyl orsimilar monovalent hydrocarbon radical. By means of suitable alkylatingagents, one may introduce alkyl groups, aryl radicals, aralkyl radicals,alicyclic radicals, hydroxy hydrocarbon radicals, and the like.Convenient reagents for such reactions include alkyl chlorides, such asbutyl chloride, benzyl chloride, phenyl chloride, ethyl bromide,glycerol chlorhydrin, ethylene chlorhydrin, ethylene oxide, propyleneoxide, diethyl sulfate, ethyl chloraceta-te, etc. The result of analkylation reaction or the equivalent usually results in the formationof an amine salt, such as the amine hydrochloride. The liberation of thefree amine depends upon conventional treatment with caustic soda or thelike. Treatment with a reactive alkylene oxide, such as ethylene oxide,propylene oxide, and the like does not result in the formation of asalt, and thus in many ways is a more suitable procedure. It should benoted that the hydroxyl, which is part of the radical H.D, is reactivetowards alkyl-ating agents. In some instances perhaps such hydroxylhydrogen atom is more reactive than in the amino hydrogen atom,

and perhaps inother instances not so reactive. The speed of thereactions depends, of course, on the reactants selected and theconditions of the reaction. However, it is to be noted that suchreaction may result in the formation of an ether group. This may beillustrated by involving a butyl chloride and a hydroxyl hydrogen atom,thus:

C4HD: (;i :'E :}O.D

CNH2

In this instance the radical C4H9.O.D. represents an alkoxyalkylradical, in which D might be obtained from any one of the aldehydesmentioned, for example, acetaldehyde or butyraldehyde; and the butylradical might be replaced by some other radical, such as the hexylradical, benzyl radical, cyclohexyl radical, or the like.

If ethylene oxide, propylene oxide, or the like are used to react withthe hydrogen atom previously referred to, then the reaction proceeds asfollows:

H H noon+no.n alkyl onczmop alkyl o C-N\- /C-N\ I 011.1) alkyl 011.1)alkyl Thus, examining the class of amine compounds in the broadestaspect, they may be rewritten as:

in which B represents a monovalent hydroxy hydrocarbon radical,preferably an alkylol radical, or may be a monovalent oxyhydrocarbonradical, in which the carbon atom chain is interrupted at least once byan oxygen atom, or may be a hydroxylated oxyhydrocarbon radical, which,in addition to having at least one hydroxyl radical, has the carbon atomchain interrupted at least once by an oxygen atom. Reactants such asglycerol monochlorhydrin, or the corresponding chlorhydrins derived fromdior triglycerol, would permit the introduction of radicals containingmore than one hydroxyl group, and being interrupted more than once by anoxygen atom. T may be the same as B, or may be a hydrogen atom or anyalkyl radical. Z represents a hydrogen atom, or may represent anymonovalent hydrocarbon radical, hydroxy hydrocarbon radical, hydroxyoxyhydrocarbon radical characterized by having a hydroxyl radical, andhaving a carbon atom chain interrupted at least once by oxygen, or aradical derived by hypothetical removal of an alpha hydrogen atom from acarboxy acid ester. It is to be noted that the pre ferred amine is ofthe type which contains no aryl radicals, particularly no aryl radicalsattached to the amino nitrogen atom, and is preferably of the primaryamine type. Due to its availability, the amine which we prefer to employis tris (hydroxymethyl) aminomethane.

It is obvious, in view of what has been said, that the intermediateacylation products obtained may be of the type in which all acylradicals present are in the amido form. Compounds may be of the type inwhich all acyl radicals present are in the ester form. It is alsopossible to have a series of compounds which exhibit both the amido formand the ester form. Furthermore, it is obvious that an amine of the kindcontemplated cannot react with a ricinolcic acid body to'glve anintermediate acylation product, unless there is present either analcoholiform hydroxyl, or. an amino hydrogen atom. Of course, both formsof reactive hydrogen atoms may be present, a hydrogen of the alcoholradical being referred to as a reactive hydrogen atom. With this inmind, in the hereto appended claims the expression acylation-reactiveamine is employed to designate such amine, which is reactive in regardto acylation reactions of the kind described.

As is apparent to a person skilled in the art of acylation reactionsofthe kind referred to, one can select reactants and conditions ofreaction, so as to obtain primarily one particular type or primarilyanother particular type. These variations will be described in some ofthe following examples:

Intermediate product, Example 1 Intermediate product, Example 2 Amolecular proportion of tris(hydroxymethyDmethyl butylamine is treatedwith 1 mole of ricinoleic acid and heated until one obtains an esterwith the elimination of water.

Intermediate product, Example 3 A -molecular proportion oftris(hydroxymethyDmethyl butylamine is treated with one mole of ethylricinoleate. The esters preferentially react with replacement of anamino hydrogen atom, rather than an alcoholiform hydroxyl hydrogen'atom.Thus, the above reaction can be conducted in a manner to produce theamide in almost complete absence of the ester.

Intermediate product, Example 4 One mole of tris(hydroxymethy1)aminomethane is treated with one mole of ricinoleoamide in theconventional manner to eliminate ammonia and form the ricinoleic acidamide of tris(hydroxymethyl) aminomethane.

Intermediate product, Example 5 One molecular proportion of.tris(hydroxymethyDaminomethane is treated with two moles of ricinoleicacid until one forms the amide ester. Theoretically one can form asecondary amide, i. e., an amide in which two amino hydrogen atomsattached to the same amino nitrogen atom have been replaced by an acylradical. However,

. the introduction of the second amide group attached to the same aminonitrogen is rather difficult to obtain under ordinary conditions ofreaction"; and thus actually one introduces the second acyl group in theester form.

Intermediate product, Example 6 Tris(butyloxymethyl) aminomethane istreated with one mole of ricinoleic acid to form the corresponding amideof the following formula:

OC.R

((341190 CII:):iC--N in which OCR represents the acyl radical derivedfrom ricinoleic acid. If a slightly additional amount of ricinoleic acidis employed, and if conditions producing acylation are raised to a pointHowever, other means may be employed to obtain predominantly one type orthe other. For instance, if one has the amide or a mixture of the amideand ester type, one can convert the same to the ester type by reactionwith a dilute acid. The reason such procedure can be employed is thatapparently there is an equilibrium between the amide type and the estertype, especially when heated; and the ester type is basic and dissolvesin the acid, thus upsetting the equilibrium. For instance, reference ismade to U. S. Patent No. 2,151,788, dated March 28, 1939, toMauersberger, in which such conversion is illustrated, for. instance, inconnection with an amide derived from monoethanolamine and oleic acid byuse of lactic acid. Such procedure is appli-.- cable in connection withthe compounds herein contemplated.

Having obtained an esterified amine or an amide or an ester amine of thekind above described, or a mixture of such compounds, the next step isto react the same with a polybasic carboxy acid or its equivalent, suchas an anhydride, acyl chloride, or the like. Suitable polybasic carboxyacids include phthalic acid, succinic, maleic, fumaric, citric, maleic,adipic, tartaric, glutaric, diphenic, naphthalic, oxalic, pimelic,suberic, azelaic, sebacic, etc. In the following examples we explain indetail how our new composition of matter maybeproduced:

Example 1 The method of reaction for forming said new composition ofmattcr is such as preferably to involve a hydroxyl of an esterifiedamine, or an ester amide. involve the alcoholiform hydroxyl of thericinoleyl radical, or may involve a hydroxyl attached to an alkylradical or the like, such as the hydroxyl of a methylol radical.

, ploy any of the intermediate products previously described. Ourpreference is to use a product of the kind described under the heading,Intermediate product, Example 1, above. Phthalic anhydride is added tosuch material in such proportion that one employs one mole of theanhydride for each ricinolcyl radical present. If desired, an increasedamount of phthalic anhydride may be employed. For instance, one mayemploy two moles of phthalic anhydride instead of one mole. The mixtureof the materials just described, i. e., the intermediate raw materialand phthalic anhydride in predetermined proportions, are added at atemperature of approximately -180 C. until all free phthalic anhydridehas disappeared. At this point one has formed a compound characterizedby the fact thatthere is one free phthalic acid carboxyl present foreach mole of phthalic anhydride employed. This stage of reaction isindicated by a determination of theaci d In other words, the reactionmay It is understood,

value. The nature of the compound obtained depends upon the time ofreaction, temperature of reaction, and the molal ratios employed. Inother words, one may obtain esterification reactions to a greater degreeunder one set of circumstances, and perhaps acylation reactions to agreater degree under slightly different circumstances. It is alsoobvious that one may employ raw materials of the kind described, inwhich there are no amino hydrogen atoms present; and thus, one obtainsno acylation reactions. Under such circumstances the reactions would bestrictly of the esterification type.

The final product, which may be a viscous or semi-resinous orsub-resinous material, may be employed as such, or may be diluted withany suitable solvent of the kind hereinafter described.

Example 2 Maleic acid is substituted for phthalic anhydride in theprevious example.

Example 3 Succinic acid is substituted for phthalic anhydride in Example1.

Example 4 an intermediate raw material of the kind described under theheading Intermediate product, Example 4, preceding, is substituted forIntermediate product, in Examples 1-3 preceding.

Example 5 A material of the kind described under the headingIntermediate product, Example 5, preceding, is substituted as a rawmaterial for Intermediate product, in Examples 1-3 preceding.

Example 6 The intermediate material described under the headingIntermediate product, Example 6", preceding, is substituted forIntermediate product, in Examples 1-3 preceding.

Example 7 Types of the kind exemplified by Examples 1-6 preceding areprepared employing amounts of a dibasic acid so that there are residualcarboxylic radicals. The acidity of the product is determined by theconventional method of determining an acid number. An amount oftriethanola mine is added to neutralize the acidity.

Example 8 I The same procedure is followed as in Example 7 preceding,except that diethanolamine is employed.

- Example 9 The same procedure is employed as in Example 7, exceptv thatthe product isheated so as to convert the triethanolamine salt into anester by reaction involving the carboxylic hydrogen atom of the dibasicacid and a hydroxyl of the ethanol group of the triethanolamine.

Example 10 upon following the exact procedure previously outlined. Incertain instances the other reactants might be employed, or elsereactants of the kind previously described might be combined in someother manner. It is not intended that the hereto appended claims belimited in any manner whatsoever as to the method of manufacture, unlesssuch method is specifically recited.

In such instances where the ricinoleic acid acylation product (an amide,amino or esterified amine) contains at least two hydroxyl radicals, orat least two amino hydrogen atoms, or at least one hydroxyl and at leastone amino hydrogen atom, then one is dealing with a polyfunctional orbifunctional compound, and thus reactions involving such types ofcompounds with a polybasic or dibasic acid, such as phthalic anhydride,will produce a sub-resinous or a semi-resinous type of material. Compareanalogous reactions involving glycerol or glycol or monoethanolamine anddibasic or polybasic acids. Our preferred reagent is derived from anamine of the kind which is polyfunctional, and ismost desirably of thesub-resinous type; in other words, a compound or mixture of compoundswhich still represents a liquid or plastic or fusible mass at atemperature at which the final reaction is completed, and is soluble inone or more solvents which may be hydrophile or hydrophobe in nature,including solutions of an acid, such as acetic acid, hydrochloric acid,etc.

Certain obvious functional equivalents suggest themselves and need notbe described in detail. For instance, a halogenated ricinoleic acid bodymight be employed just as advantageously as an ordinary ricinoleic acidbody. No advantage would be obtained by the use of more expensive rawmaterial. Similarly, chlorinated phthalic anhydride or acid might beused in place of the less expensive raw material.

It is hardly necessary to indicate that various members of the classpreviously described are characterized by the presence of a. basic ormoderately basic amino nitrogen atom, for instance, the ester type. Suchbasic type of compound naturally can be used as such (without reactionwith water); or it can be used in the form of a base, i. e., thecompound derived by reaction with water, or in the'form of a salt, forinstance, the acetate or the salt derived by reaction with a strongmineral acid, such as hydrochloric acid or the like.

We desire to emphasize that the expressions polybasic carboxy acid anddibasic carboxy acid, used in the claims, refer not only to the acidsthemselves, but to any functional equivalent, such as the anhydride, theacyl chloride, 8. salt form having at least two free carboxyls, such asmonosodium citrate, etc.

It is also understood that in the hereto appended claims the nature ofthe final product is not limited to the form having a free carboxylichydrogen, but that such free carboxylic hydrogen may actually bereplaced by any functional equivalent of the kind previously described,for instance, a metallic atom, an ammonium radical, an amine radical,such as an amylamine radical, benzylamine radical, ethanolamine radical,diethanolamine radical, triethanolamine radical, a hydrocarbon radical,such as an ethyl, methyl, propyl, or amyl radical, a radical derivedfrom ethylene glycol, glycerol, or the like; a cyclohexyl radical,benzyl radical, etc. All such forms in which such ionizable hydrogenatom equivalent replaces an ionizable hydrogen atom, are obviousfunctional equivalents. Attention is directed to the fact that the wordamidification has been applied to the reaction involving the replacementof an amino hydrogen atom by an acyl radical without conventionallimitation to a reaction involving ammonia. The replacement of the aminohydrogen atom of a primary amine or a secondary amine by an acyl radicalhas been considered as being amidification, rather than the formation ofa substituted amide, or the formation of an imide or substituted imide.Such obviousdeparture from conventional nomenclature has been forpurposes of simplicity and to show the similarity between certainreactions. Chemical compounds of the kind herein described for use asdemulsifiers are also of value as surface tension depressants intheacidization of calcareous oil-bearing strata by means of strongmineral acid, such ashydrochloric acid.

Conventional demulsifying agents employed in the treatment of oil fieldemulsions are used as such, or after dilution with any suitable solvent,such as water, petroleum hydrocarbons, such as gasoline, kerosene, stoveoil, a coal tar product, such as benzene, toluene; xylene, tar acid oil,cresol, anthra-cene oil, etc. Alcohols, particularly aliphatic alcohols,such as methyl alcohol, ethyl alcohol, denatured alcohol, propylalcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may beemployed as diluents. Miscellaneous solvents, such as pine oil, carbontetrachloride, sulfur dioxide extract obtained in the refining ofpetroleum, etc., may be employed as diluents. Similarly, the newcomposition of matter previously described, and intended to be used asthe demulsifying agent of our process, may be admixed with one or moreof the solvents customarily used in connection with conventionaldemulsifying agents. Moreover, said new material or composition' ofmatter may be used alone, or in admixture with other suitable well knownclasses of demulsifying agents.

It is well known that conventional demulsifying agents may be used in awater-soluble form, or inan oil-soluble form, or in a form exhibitingboth oil and water solubility. Sometimes they may be used in a formwhich exhibits relatively limited oil solubility. However, since suchreagents are sometimes used in a ratio of 1 to 10,000, orl to 20,000, oreven 1 to 30,000, such an apparent insolubil'ity in oil and wateris notsignificant, because said reagents undoubtedly have solubility withinthe concentration employed. This same fact is true in regard to the newmaterial or composition of matter employed as the demulsifying agent ofour process.

We desire to point out that the superiority of the reagent ordemulsifying agent contemplated in our process is based upon its abilityto treat certainemulsions more advantageously and at a somewhat lowercost than is possible with other available demulsifiers, or conventionalmixtures thereof. It is believed that the particular demulsifying agentor treating agent herein described will find comparatively limitedapplication, so far as the majority of oil field emulsions areconcerned; but we have found that such a demulsifying agent hascommercial value, as it will economically break or,resolve oil fieldemulsions in a number of cases which cannot be treated as easily or atso low a cost with the demulsifying agents heretofore available.

In practising our process, a treating agent or demulsifying agentconsisting of the new material or composition of matter above described,is brought into contact with or caused to act upon the emulsion to betreated, in any of the various ways, or by any of the various apparatusnow generally used to resolve or break petroleum emulsions with achemical reagent, the above procedure being used either alone, or incombination with other demulsifying procedure, such as the electricaldehydration process.

The demulsifier herein contemplated may be employed in connection withwhat is commonly known as down-the-hole procedure, i. e., bringing thedemulsifier in contact with the fluids of the,

well at the bottom of the well, or at some point prior to theiremergence. This particular type of application is decidedly feasiblewhen the demulsifier is used in connection with acidification 0fcalcareous oil-bearing strata, especially if suspended in or dissolvedin the acid employed I B z in which B is selected from the classconsisting of hydroxy hydrocarbon radicals, ether-type oxyhydrocarbonradicals, and hydroxylated ether-type oxyhydrocarbon radicals; T isselected from the class consisting of hydrogen atoms, alkyl radicals,and radicals of the kind exemplified by B; and Z represents a member ofthe class consisting of hydrogen atoms, hydrocarbon radicals,oxyhydrocarbon radicals, and radicals derived by removal of an alphahydrogen atom from a carboxy acid ester.

2. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a sub-resinousdemulsifler comprising a product of the kind derivable by an acylationreaction between: first, a polybasic carboxy acid; and second, theproduct of an acylation reaction between a ricinoleic acid body and anacylation reactive amine of the type:

B z B t Z in which B is selected from the class consisting ,0! hydroxyhydrocarbon radicals, ether-type oxy-v derivable by an acylationreaction between: first, a dibasic carboxy acid; and second, the productof an acylation reaction between a ricinoleic acid body and an acylationreactive amine of the type:

in which B is selected from the class consisting of hydroxy hydrocarbonradicals, ether-type oxyhydrocarbon radicals, and hydroxylatedether-type oxyhydrocarbon radicals; T is selected from the classconsisting of hydrogen atoms, alkyl radicals, and radicals of the kindexemplified by B; and Z represents a member of the class consisting ofhydrogen atoms, hydrocarbon radicals, oxyhydrocarbon radicals, andradicals derived by removal of an alpha hydrogen atom from a carboxy Iacid ester.

4. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a sub-resinousdemulsifier comprising a product of the kind derivable by an acylationreaction between: first, maleic anhydride; and second, the product of anacylation reaction between a ricinoleic acid body and an acylationreactive amine of the type:

acid ester.

5. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of asiib-resinous demulsifier comprising a product of the kind derivable byan acylation reaction between: first,

oxalic acid; and second, the product of an acyla- I tion reactionbetween a ricinoleic acid body and an acylation reactive amine of thetype:

in which B is selected from the class consisting of hydroxy hydrocarbonradicals, ether-type oxyhydrocarbon radicals, and hydroxylated ethertypeoxyhydrocarbon radicals; T is selected from the class consisting ofhydrogen atoms, alkyl radicals, and radicals of the kind exemplified byB; and Z represents a member of the class consisting of hydrogen atoms,hydrocarbon radicals, oxyhydrocarbon radicals, and radicals derived byremoval of an alpha hydrogen atom from a carboxy acid ester.

6. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a sub-resinousdemulsifier comprising a product of the kind derivable by an acylationreaction between: first, phthalic anhydride; and second, the product ofan acylation reaction between a ricinoleic acid body and an acylationreactive amine of the type:

in which B is selected from the class consisting of hydroxy hydrocarbonradicals, ether-type oxyhydrocarbon radicals, and hydroxylated ethertypeoxyhydrocarbon radicals; T is selected from the class consisting ofhydrogen atoms, alkyl radicals, and radicals of the kind exemplified byB; and Z represents a member of the class consisting of hydrogen atoms,hydrocarbon radicals, oxyhydrocarbon radicals, and radicals derived byremoval of an alpha hydrogen atom from a carboxy acid ester.

'7. A process for breaking petroleum emulsions of the Water-in-oil type,characterized by subjecting the emulsion to the action of a sub-resinousdemulsifier comprising a product of the kind derivable by an acylationreaction between: first, phthalic anhydride; and second, the product ofan acylation reaction between a ricinoleic acid body and an acylationreactive amine of the type:

in which B is an alkylol radical; T is selected from the classconsisting of hydrogen atoms, alkyl radicals, and radicals of the kindexemplified by B; and Z represents a member of the class consisting ofhydrogen atoms, hydrocarbon radicals, oxyhydrocarbon radicals, andradicals derived by removal of an alpha hydrogen atom from a carboxyacid ester.

8. A process for breaking petroleum emulsions of the Water-in-oil type,characterized by subjecting the emulsion to the action .of asub-resinous demulsifier comprising a product of the kind derivable byan acylation reaction between: first, phthalic anhydride; and second,the product of an acylated reaction betwen a ricinoleic acid body andtris(hydroxymethyl) aminomethane.

9. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a sub-resinousdemulsifier comprising a product of the kind derivable by an acylationreaction between: first, phthalic anhydride; and second, th product ofan acylated reaction between a ricinoleic acid body andtris(hydroxymethyl)aminomethane;

said acylation product being primarily of the amide type.

10. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsifiercomprising a product of the kind derivable by an acylation reactionbetween: first, phthalic anhydride; and second, the product of anacylated reaction between a ricinoleic acid body and tris(hydroxymethyl)aminomethane; said acylation product being primarily ofthe ester type.

11. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a sub-resinousdemulsifier comprising a product of the kind derivable by an acylationreaction between: first, phthalic anhydride; and second, the product ofan acylated reaction between a ricinoleic acid body andtris(hydroxymethyl) aminomethane; said acylation product being primarilyof the ester amide type.

MELVIN DE GROO'I'E. BERNHARD KEISER.

CERTIFICATE OF CORRECTION. Patent No. 2,2 o,to6. July 22, 191;.1.

MELVIN DE GROOTE, ET AL.

It is hereby certified that error appears in the. printed specificationof the "above numbered patent requiring correction as follows; Page 2,first column, line 11.1, beginning with "he'xahydrobenzaldehyde" strikeout all to and including "yields" in line 14.7, afid insert instead thefollowing the like. Of various aldehydes employed for reaction with the.nitroparaffins formaldehyde, acetaldehyde, and butyraldehyde are to bepreferred, with formaldehyde being particularly desirable. vCyclicaldehydes, such as benzaldehyde, or hexahydrobenzaldehyde, give veryinferior yields page 6 second column, line 57, claim 10, before thesyllable "demulsi" insert "sub-resinous"; and that the said LettersPatent should be read with this correction therein that the same mayconform to the record of the case in the Patent Office. 7

Y Signed and sealed this 28th day of October, A,D.- 19in.

Henry Van Arsdale,

(Seal) Acting Commis sioner of Patents.

CERT-IFICATEOF CORRECTION. Patent No. 2,25O, l4.06. July -22, 19L;1.

MELVIN DE 'GROOTE, ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 2,first column, line 141, beginning with "he'xahydrobenzaldehyde" strikeout all to and including "yields" in line in, aid insert instead thefollowing the like, of various aldehydes employed for reaction with the'nitroparaffins, formaldehyde, acetaldehyde, and butyral'dehyde are tobe preferred, with formaldehyde being particularly desirable. .Cyclicald'ehydes, such asbenzaldehyde, or lhexahydrobenzaldehyde, give veryinferior yields page 6 second column, line 57, claim l0, before thesyllable "demulsi insert --subresinous--; and that the said LettersPatent should be read 7 with this correction therein that the same mayconform to the record of the case in the Patent Office.

, Signed and sealed this 28th day of. October, A,D 19141.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents.

